312 



BULLETIN OF THE 



not crenulate the varices; shell imperforate, without basal disk or cordon; 

 aperture small, lip thin, narrow, hardly reflected, tortuous and a little patulous 

 at the anterior end of the axis; suture very deep. Lon. 30.0, max. lat. 

 6.5 mm. 



Habitat. U. S. Fish Commission Station 2678, in 731 fms., light gray ooze, 

 bottom temperature 38°.7 F. 



The specimen procured was fresh, but without the soft parts. This beautiful 

 species somewhat resembles Verrill's figure of S. Dalliana, but is longer, much 

 more cylindrical, and has strong spiral sculpture which is wanting in that 

 species. The upper fourth of S. babylonia^ which would about correspond in 

 size to S. Dalliana, has the costa) more sparse, thin and erect, the whorls much 

 rounder, and the suture much deeper than in that species. None of the other 

 species described from deep water are much like it. 



Scala ( Acrilla) retifera n. s. 



Shell small, thin, yellowish or grayish, with ten ordinary and three pol- 

 ished dark brown smooth nuclear whorls; apex acute, whorls well rounded, 

 suture distinct; whorls closely reticulated by (on the last about twenty-five) 

 little-elevated thin transverse lamellae, and five strong, even, regular revolving 

 or spiral ribs over which the lamella) are fluted and frilled with great regularity. 

 The lamell39 pass from the suture to the margin of the very large basal disk, 

 over the edge of which they pass as slightly raised lines centring at the axis of 

 the shell, and giving a wheel-like appearance to the disk, which is also sculp- 

 tured by fine radiating and stronger revolving threads; the disk is a little con- 

 cave, and like the rest of the shell tinged with brownish yellow, but the 

 columella or axis is pure white, polished, and shows a single strong spiral fas- 

 ciole; the lip is thin, hardly at all reflected, the margin is angulated by the 

 carina of the disk and at the somewhat projecting columella so that the aper- 

 ture has a squarish appearance. The whole base from the suture down is 

 occupied by the disk. Lon. 12.5, max. lat. 4.3 mm., of the largest specimen. 



Habitat. Seventeen to twenty-five miles off the coast of North Carolina, at 

 U. S. Fish Commission Stations 2595 and 2596, in 49 to 63 fms., sand, bottom 

 temperature 75°.0 F. 



This very pretty species is related to Acrilla decussata of Lamarck as iden- 

 tified by M. de Boury. This differs from S. retifera in its smaller and less 

 emphasized basal disk, its much more numerous and less regular spiral striae, 

 and raised threads which do not flute the transverse lamella?. S. decussata 

 appears also to reach a much larger size. There is no other recent species 

 which is at all like S. retifera, so far as T have been able to discover. Sowerby's 

 figure of decussata is not unlike S. retifera, but it does not represent the origi- 

 nal decussata of Lamarck, which is a fossil species. 



